Diffusion transfer process for photographic silver halide emulsion

ABSTRACT

WHEREIN X IS A LOWER ALKENYL OR A LOWER ALKENOXY GROUP, R1 IS HYDROGEN, OR A LOWER ALKYL GROUP, AND R2, R3 AND R4 EACH IS HYDROGEN, A LOWER ALKYL GROUP, A LOWER ALKENYL GROUP OR A LOWER ALKOKY GROUP, IN WHICH THE TERM &#34;LOWER&#34; INDICATES THAT THE TOTAL NUMBER OF CARBON ATOMS CONTAINED IS NOT MORE THAN 4.   2-X,3-R2,4-(R1-NH-),5-R3,6-R4-PHENOL   A HIGH SPEED DIFFUSION TRANSFER PROCESS WHICH COMPRISES PROCESSING AN EXPOSED PHOTOGRAPHIC SILVER HALIDE MATERIAL WITH A PROCESSING SOLUTION CONTAINING A COMPOUND REPRESENTED BY THE FOLLOWING GENERAL FORMULA OR ACID SALT THEREOF:

United States Patent DIFFUSION TRANSFER PROCESS FOR PHOTO- GRAPHICSILVER HALIDE EMULSION Haruhiko Iwano, Mitsugu Tanaka, Tetsuo Otsuki,and Atsuaki Arai, Kanagawa, Japan, assignors to Fuji Photo Film Co.,Ltd., Kanagawa, Japan N0 Drawing. Filed June 8, 1971, Ser. No. 150,932Claims priority, application Japan, June 8, 1970, 45 49 338 Int. (:1.GflSc 5/54 US. Cl. 96-29 12 Claims ABSTRACT OF THE DISCLOSURE A highspeed diffusion transfer process which comprises processing an exposedphotographic silver halide material with a processing solutioncontaining a compound represented by the following general formula oracid salt thereof:

term lower indicates that the total number of carbon atoms contained isnot more than 4.

FIELD OF THE INVENTION The present invention relates to a process forprocessing an exposed photographic silver halide light-sensitivematerial. More particularly, the present invention relates to a processfor processing exposed silver halide photographic material by diffusiontransfer process.

In diffusion transfer process, a latent image formed in a negativeemulsion layer by imagewise exposure is developed and, simultaneously, aresidual unexposed silver halide, i.e., undeveloped silver halide, inthe negative emulsion layer, is reacted with a silver halide solvent toform a soluble silver complex in an amount corresponding to the amountof the exposure. Such soluble, silver complex is reduced in aprint-receiving layer which is brought into contact with the exposedsilver halide emulsion layer and contains a suitable silverprecipitating layer, whereby the reduced silver is precipitated to givethe desired positive image.

OBJECT OF THE INVENTION An object of the present invention is to preparea processing solution for a high speed diffusion transfer process, whichis suitable for forming satisfactory images from a silver halideemulsion exposed to a small quantity of light, for example, of exposureindex ASA 1,000.

The processing solution to be employed in the diffusion transfer processaccording to the present invention is a viscous liquid which isuniformly spread between the negative and positive layers, and developsa latent image in the silver halide emulsion layer, even when formed bya small quantity of exposure index more than ASA 1,000, followed by thesame step as above to form positive images. Moreover, it is desirable tofinish the processings to form the positive image within short periodsof time, that is, within 1 minute.

Therefore, in the high speed diffusion transfer process as describedabove, it is necessary to use a highly active developing agent todevelop rapidly a weak latent image formed by little exposure.Furthermore, as the solvent for silver halide to form a soluble silvercomplex there "ice are thiosulfates, thiocyanates and the like. Inaddition, there may be added into the processing solution alkalineagents, normally employed additives, such as potassium bromlde, andantifoggants such as 6-nitro-benzimidazole, as well as aviscosity-increasing agent, such as carboxymethyl cellulose,hydroxyethyl cellulose and the like.

An object of the present invention is to prepare a processing solutionfor use in a high speed diffusion transfer process which is suitable forthe purpose of forming a satisfactory positive image from a silverhalide emulsion which has been exposed to small quantities of light, forixgrple, to light showing an exposure index of ASA More particularly,this invention provides highly active developing agents suitable for usein processing solutions employed in the above-described high speeddiffusion transfer process.

DESCRIPTION OF THE PREFERRED EMBODIMENT Thus, it has now been found thatthe above objects can be attained by a developing agent represented bythe following formula:

wherein X is a lower alkenyl or a lower alkenoxy group, R is hydrogen ora lower alkyl group, and R R and R each is hydrogen, a lower alkylgroup, a lower alkenyl group, or a lower alkoxy group, the term lowerindicating that the total number of carbon atoms is not more than 4.

The compounds of the above-described formula to be employed according tothe present invention may be used in either the form of a free amine, asshown by the general formula itself, or in the more stable form of acidaddition salts, such as sulfates and hydrochlorides.

Although many analogous p-aminophenols such as Metol (i.e.,N-methyl-p-aminophenol sulfate) have been known and practicallyemployed, the compounds of the above-described general formula arecharacterized by having a substituent X, and it has now been found thatthe combination of these compounds with the high diffusion transferprocess can afford particularly preferred results.

As described above, the images obtained by the high speed diffusiontransfer process using, as a developing agent, a compound of theabove-described general formula can yield a satisfactory positive image.Also, the compounds represented by the general formula are very solublein water. Since a quantity of the highly active developing agent is tobe employed in the process ng solution of the high speed diffusiontransfer process, the great solubility in water can be extremelyadvantageous.

Furthermore, the compounds of the general formula may be used singly ashighly active developing agents or may be used together with otherreducing agents, such as phenols, such as cresol, and hydroxylamines,such as N,N-diethylhydroxylamine.

In both cases, there may be obtained a good positive image by thediffusion transfer process.

As practical examples of the silver halide developing agents of theinvention, there are the following:

( l) 4-amino-2-allylphenol,

(2) 4-amino-2-allyloxyphenol,

(3) 4-amino-2,6-diallylphenol,

(4) 4-amino-2'allyl-3,S-dimethylphenol, and (5)4-methylamino-Z-allylphenol.

Typical methods for preparing the compounds of the above-describedgeneral formula are shown as follows:

Synthesis 1 (4-amino-2-allylphenol hydrochloride) While a solutionconsisting of 97 g. of sulfanilic acid, 39.2 g. of sodium carbonatemonohydrate and 1 liter of water was maintained at 8 C., 168 ml. ofconcentrated hydrochloric acid and then 40.6 g. of sodium nitritedissolved in a small amount of water were added to obtain a reactionmixture containing White diazonium salt.

The resulting mixture was added to a solution composed of 112 g. ofcaustic soda, 164 g. of sodium carbonate monohydrate, 75 g. of2-allylphenol and 2 liters of water with stirring, wherein thetemperature of the reaction mixture should be kept below C. in a waterbath. After the addition, the water bath was removed and, after stirringfor an hour, 400 g. of sodium hydrosulfite was added thereto followed byheating to 70 C. to provide precipitated white crystals of the amine.After cooling, the crystalline amine was collected and converted intoits hydrochloride, whereby 67 g. of 4-amino-2-allylphenyl hydrochloride,as colorless crystals having a melting point of from 177 to 190 C.(decomposed), was obtained in a yield of 64.4%.

Synthesis 2 (4-amino-2,fi-diallylphenol hydrochloride) In a mannersimilar to Synthesis 1, 2,6-diallylphenol was coupled with a diazoniumsalt of sulfanilic acid followed by treatment with sodium hydrosulfite.The resulting amine was converted into its hydrochloride to obtain thedesired product, as colorless needles having a melting point of from 125to 165 C. (decomposed), in a yield of 51.0%.

Synthesis 3 (4-amino-2-allyl-3,5-dimethylphenol hydrochloride) In amanner similar to Synthesis 1, 2-allyl-3,5-dimethylphenol was coupledwith a diazonium salt of sulfanilic acid followed by treatment withsodium hydrosulfite. The resulting amine was formed into itshydrochloride to obtain the desired product as colorless crystals havinga melting point of from 236 to 237 C. in a yield of 55.1%.

The developing agents represented by the general formula are very usefulas developing agents in the silver salt diffusion transfer process.

The negative materials employed in the invention may be film or paperhaving coated thereon black-white negative emulsions intended for use inusual photography or negative emulsions for use in X-ray photography.These negative emulsions contain silver halide, such as silveriodobromide, which may be spectrally and/or chemically sensitized. Inaddition, the positive materials are composed of a film or paper havingcoated thereon a layer containing nuclei of physical development. Amongsuch positive materials is, for example, a Positive Paper for Neo-Copymade by Fuji Photo Film Co., Ltd.

The use of the compounds of the general formula in the processingsolution for the high speed diffusion transfer process will be furtherillustrated by the following typical examples.

EXAMPLE 1 H O ml 500.0 Carboxymethyl cellulose (high viscosity) g 20.0Na SO g 30.0 N32520:; g NaOH g 20.0 Compound (1) (as hydrochloride) g15.0

4 After contact for about 30 seconds, the print-receiving layer wasstripped to obtain a positive image of satisfactory gradation.

EXAMPLE 2 Example 1 was repeated, except that the following processingsolution was used in place of the processing solution:

H O ml 500.0 Carboxymethyl cellulose (of high viscosity) g 20.0 Na SO;.g 30.0 Na S O g NaOH g 20.0 N,N-diethylhydroxylamine ml 25.0 Compound(1) (as hydrochloride) g 10.0

EXAMPLE 3 Example 1 was repeated, except that the processing solutionwas replaced by the following processing solution:

Example 1 was repeated, except that compound (4) was employed as thehydrochloride in place of compound (1).

EXAMPLE 5 Example 2 was repeated, except that compound (4) was employedas the hydrochloride in place of compound (1).

EXAMPLE 6 Example 3 was repeated, except that compound (4) was employedas the hydrochloride in place of compound (1).

This invention has been described in detail with particular reference topreferred embodiments thereof but it will be understood that variousvariations and modifications can be effected within the spirit and scopeof the invention as described and as defined in the appended claims.

What is claimed is:

1. A high speed difi'usion transfer process which comprises processingan exposed photographic silver halide material with a processingsolution containing a compound represented by the following generalformula or acid salt thereof:

BIO-@NHR;

wherein X is a lower alkenyl or a lower alkenoxy group, R is hydrogen,or a lower alkyl group, and R R and R each is hydrogen, a lower alkylgroup, a lower alkenyl group or a lower alkoxy group, in which the termlower indicates that the total number of carbon atoms is not more than4.

2. The process as claimed in claim 1 wherein the processing solutioncontains ingredients capable of reacting with an unexposed silver halideto form the soluble silver complexes.

3. The process as claimed in claim 1 wherein the processing solutioncontains an alkaline agent, an antifoggant and/or viscosity-increasingagent thickeners.

4. The process as claimed in claim 1 wherein said compound or the acidaddition salt thereof is employed singly in the processing solution.

5.. The process as claimed in claim 1 wherein said compound or acidaddition salt thereof is employed in combination with other reducingagents.

6. The process as claimed in claim 5 wherein said reducing agent is ahydroxylamine.

7. The process as claimed in claim 5 wherein the reducing agent isN,N-diethylhydroxylamine.

8. The process as claimed in claim 5 wherein said reducing agent is aphenol.

9. The process as claimed in claim 5 wherein the reducing agent isp-cresol.

10. The process as claimed in claim 1 wherein the compound is4-amino-2-allylphenol, or salts thereof.

11. The process as claimed in claim 1 wherein the compound is4-amino-2,6-diallylphenol, or salts thereof.

12. The process as claimed in claim 1 wherein the compound is 4 amino 2allyl-3,5-dimethylphenol, or salts thereof.

References Cited 5 UNITED STATES PATENTS 3,186,843 6/1965 Haas 9666 R2,059,887 11/1936 Man'nes et a1. 96-59 2,652,428 9/1953 Weissberger 9666X 3,108,001 10/1963 Green 96-66 10 3,241,964 3/1966 Land 96-66 R NORMANG. TORCHIN, Primary Examiner US. Cl. X.R. 15 9666 R

